Quick version
Lipoprotein(a) – or Lp(a) – is an inherited variant of the "bad" LDL cholesterol with an extra protein that increases the risk of atherosclerosis, inflammation and valve stenosis. Since the level is controlled to about 90% by genetics, it is not included in standard blood lipid tests and cannot be affected by lifestyle changes. High Lp(a) does not cause any symptoms in itself, but acts as an independent risk enhancer for cardiovascular disease. If an elevated value is detected, treatment focuses on intensively lowering other modifiable risk factors, especially LDL cholesterol and blood pressure.
Lipoprotein(a), often abbreviated Lp(a), can be elevated even in people who exercise, eat well and have “normal cholesterol” on a regular blood lipid check. This is one of the explanations why heart attacks or strokes sometimes occur unexpectedly in families where several people have been diagnosed early. This is precisely why Lp(a) has gained a clearer place in modern cardiovascular prevention, and several guidelines now recommend that the value be measured at least once in adulthood.
What is lipoprotein(a) and why is it different from regular cholesterol?
Lipoprotein(a) is a blood fat particle that is similar to LDL, what is often called “bad cholesterol.” The difference is that Lp(a) also carries an extra protein, apolipoprotein(a), which makes the particle biologically different and more linked to vascular damage.
This matters because Lp(a) not only contributes to the deposition of fat in the vascular wall. It also appears to be linked to inflammation, atherosclerosis and calcification of the aortic valve, the heart valve between the left ventricle and the body's aorta. Therefore, elevated levels are seen both with an increased risk of atherosclerotic cardiovascular disease and with aortic stenosis.
An important practical detail is that Lp(a) is not included in a standard lipid profile. You can therefore have good LDL cholesterol, normal triglycerides and still carry a hereditary risk marker that has never been discovered before.
Why is lipoprotein(a) often hereditary and difficult to influence yourself?
Unlike many other blood fats, the Lp(a) level is largely determined by genes, especially variations in the LPA gene. The level is therefore usually lifelong and is affected significantly less by diet, exercise and weight change than, for example, LDL cholesterol.
This does not mean that lifestyle habits are irrelevant to heart risk as a whole. But a person with high Lp(a) cannot 'train away' the value itself in the same way that other risk factors can sometimes be improved. It is a common patient question, especially in those who already live healthily but still have several close relatives with early heart attacks.
The level is measured in either nmol/L or mg/dL, and the two units cannot be translated exactly with a simple standard factor because the size of the particle varies between individuals. In clinical practice, levels from about 125 nmol/L or 50 mg/dL are usually considered to be at increased risk, while even higher levels imply a progressively greater risk.
For most people, one measurement in adulthood is sufficient, since Lp(a) is usually relatively stable throughout life. At the same time, more recent data have shown that some people can have clear changes over time, so if the test result is to be used in a larger risk decision, retesting may sometimes be reasonable after medical assessment.
What symptoms are caused by high lipoprotein(a) and when should you consider testing?
High Lp(a) itself does not cause any clear symptoms. You don't feel the value in everyday life, which is an important reason why it often remains undiscovered until someone in the family has a angina, heart attack, stroke or needs to be investigated for narrowing of the vessels.
What you are looking for in practice is therefore not symptoms from the blood fat particle itself, but situations where the probability of elevated Lp(a) is higher. Examples include a parent having a heart attack before retirement age, a sibling having a stroke without clear classic risk factors, or having had elevated blood lipids despite a good lifestyle.
Sampling is particularly relevant in the following situations:
- early cardiovascular disease in yourself or a close relative
- suspected or known familial hypercholesterolemia
- recurrent cardiovascular events despite treatment for LDL cholesterol
- unclearly high total risk where you want to refine the risk assessment
- aortic stenosis or early valve disease without an obvious explanation
Several current recommendations go further than that and advocate that all adults test Lp(a) at least once in their lives. The reason is that the value can identify people whose long-term risk is otherwise underestimated by common risk calculators and standard tests.
How does lipoprotein(a) affect the risk of cardiovascular disease?
Research strongly suggests that Lp(a) is an independent risk factor for atherosclerotic cardiovascular disease. This means that the association remains even when other risk factors such as LDL cholesterol, blood pressure, diabetes and smoking are taken into account.
The increase in risk is also dose-dependent. The higher the level, the greater the likelihood of future heart attacks, ischemic strokes, peripheral vascular disease and calcification of the aortic valve. People with very high levels may therefore have a lifelong risk burden that begins long before the first symptom occurs.
This helps to explain a clinical pattern that many recognize: a seemingly healthy person in their 40s or 50s is informed of narrowing of the coronary arteries, even though normal cholesterol values have not been dramatically different. If Lp(a) then turns out to be significantly elevated, the risk picture becomes more understandable, and the need to lower other modifiable risk factors becomes clearer.
Lp(a) alone is not decisive. The actual risk is shaped by the sum of several factors: blood pressure, LDL, blood sugar, tobacco use, kidney function, heredity and age. However, a high Lp(a) shifts the risk curve upwards, which means that the same LDL level or the same blood pressure may be less “acceptable” in that particular person. That is why doctors use Lp(a) as a risk amplifier in the overall assessment.
What can be done if lipoprotein(a) is elevated?
The first step is not to chase a perfect Lp(a) value, since there is still no widely available drug with an approved indication specifically for lowering Lp(a) and at the same time a proven effect on severe outcomes in routine care. Instead, treatment usually focuses on reducing the overall cardiovascular risk, especially by lowering LDL cholesterol more consistently than might otherwise have been done.
Instead, more intensive treatment with statins is required, sometimes in combination with other lipid-lowering drugs, and PCSK9 inhibitors are used to lower LDL cholesterol and reduce the overall risk.
In particular high-risk cases, lipoprotein apheresis may be considered. It is a resource-intensive treatment in which the blood is filtered to lower Lp(a) and LDL, and it is only used for selected patients at very high risk.
At the same time, new drugs are being developed rapidly that directly target apo(a) production. RNA-based treatments such as pelacarsen and olpasiran have shown significant reductions in Lp(a) in studies, but the crucial question is still whether this also leads to fewer heart attacks, strokes and other cardiovascular events in large outcome studies.
For the individual, it often makes the most sense to do three things immediately:
- map the entire risk profile with blood lipids, blood pressure, blood sugar and family history
- treat all modifiable risk factors without waiting for symptoms
- have close relatives consider testing if the value is clearly elevated
An elevated Lp(a) is not a message that disease is inevitable. It is rather an opportunity to discover a hidden risk in time, before it has time to become an acute problem. Those who know their hereditary profile can make more precise decisions about follow-up, treatment and relatives who may also need to be tested.
